Revision 928591 of CSS

<p><span class="seoSummary"><strong>Cascading Style Sheets </strong>, muitas vezes abreviado como <strong> CSS </strong>, é uma linguagem (<a href="/en-US/docs/DOM/stylesheet">stylesheet</a><a>) usada para descrever a apresentação de um documento escrito em </a><a href="/en-US/docs/HTML" title="The HyperText Mark-up Language"> HTML </a></span> ou <a href="/en-US/docs/XML" title="en-US/docs/XML"> XML </a> (incluindo várias linguagens XML como <a href="/en-US/docs/SVG" title="en-US/docs/SVG">SVG</a> ou <a href="/en-US/docs/XHTML" title="en-US/docs/XHTML">XHTML</a>). CSS é responsável por descrever como a estrutura de cada elemento precisa ser renderizado na tela, materiais impressos ou qualquer outra mídia.</p>

<p><strong>CSS </strong> é uma das principais linguagens a <em> open web </em> e é regulamentada pela <a class="external" href="https://w3.org/Style/CSS/#specs"> W3C </a>. Desenvolvida em níveis, CSS1 está obsoleto, CSS2.1 é recomendado; enquanto, <a href="/en-US/docs/CSS/CSS3" title="CSS3">CSS3</a> está em constante desenvolvimento e regulamentação.&nbsp;</p>

<section id="sect1">
<ul class="card-grid">
 <li><span>CSS Reference</span>

  <p><a href="/en-US/docs/Web/CSS/Reference" title="en-US/docs/CSS/CSS_Reference">Referência detalhada </a> para programadores, apontando todas as propriedades e conceitos.</p>
 </li>
 <li><span>CSS Tutorial</span>
  <p>Um <a href="/en-US/docs/CSS/Getting_Started" title="en-US/docs/CSS/Getting_Started"> passo-a-passo </a> para ajudar iniciantes. Aqui são apresentados todos os fundamentos básicos.</p>
 </li>
 <li><span>CSS3 Demos</span>
  <p>Uma <a href="/en-US/demos/tag/tech:css3" title="https://developer.mozilla.org/en-US/demos/tag/tech:css3">coleção de demos</a> que mostram as práticas&nbsp;mais avançadas: um empurrão na sua&nbsp;criatividade.</p>
 </li>
</ul>

<div class="row topicpage-table">
<div class="section">
<h2 class="Documentation" id="Documentation" name="Documentation">Documentação e tutoriais</h2>

<dl>
 <dt>CSS conceitos importantes</dt>
 <dd>Describes the <a href="/en-US/docs/CSS/Syntax" title="/en-US/docs/CSS/Syntax">syntax and forms of the language</a> and introduces fundamentals like <a href="/en-US/docs/CSS/Specificity" title="Specificity">specificity</a> and <a href="/en-US/docs/CSS/inheritance" title="inheritance">inheritance</a>, the <a href="/en-US/docs/CSS/box_model" title="Box model">box model</a> and <a href="/en-US/docs/CSS/margin_collapsing" title="Margin collapsing">margin collapsing</a>, <a href="/en-US/docs/CSS/Understanding_z-index/The_stacking_context" title="The stacking context">stacking</a> and <a href="/en-US/docs/CSS/block_formatting_context" title="block formatting context">block-formatting</a> contexts, or the <a href="/en-US/docs/CSS/initial_value" title="initial value">initial</a>, <a href="/en-US/docs/CSS/computed_value" title="computed value">computed</a>, <a href="/en-US/docs/CSS/used_value" title="used value">used</a> and <a href="/en-US/docs/CSS/actual_value" title="actual value">actual</a> values. Entities like <a href="/en-US/docs/CSS/Shorthand_properties" title="CSS/Shorthand_properties">CSS shorthand properties</a> are also defined.</dd>
 <dt><a href="/en-US/docs/Web/Guide/CSS" title="/en-US/docs/Web/Guide/CSS">CSS developer guide</a></dt>
 <dd>Articles to help you learn everything from the basics of styling HTML with CSS to assorted <strong>CSS</strong> techniques to make your content shine.</dd>
 <dt><a href="/en-US/docs/Web/CSS/Common_CSS_Questions">Common CSS questions</a></dt>
 <dd>Answers to common questions about <strong>CSS</strong>.</dd>
</dl>
</div>

<div class="section">
<h2 class="Tools" id="Tools" name="Tools">Ferramentas para desenvolvimento CSS</h2>

<ul>
 <li><a class="external" href="https://jigsaw.w3.org/css-validator/">W3C CSS Validation Service</a>&nbsp;checa se o seu arquivo CSS é válido. Você pode tentar também o&nbsp;<a href="//www.OnlineWebCheck.com/">OnlineWebCheck.com</a>.&nbsp;Essas ferramentas são fundamentais para debugging.</li>
 <li><a href="/en-US/docs/Tools">Firefox Developer Tools</a> allow viewing and editing live CSS of a page via the <a href="/en-US/docs/Tools/Page_Inspector">Inspector</a> and <a href="/en-US/docs/Tools/Style_Editor">Style Editor</a> tools.</li>
 <li><a class="link-https" href="https://addons.mozilla.org/en-US/firefox/addon/1843">Firebug extension</a> for Firefox, a popular extension of that navigator that allows to edit live CSS on watched sites. Very practical to test some changes, though this extension does much more.</li>
 <li><a class="link-https" href="https://addons.mozilla.org/en-US/firefox/addon/60">Web Developer extension</a> para Firefox também permite observar e editar CSS. É mais simples que o Firebug porém, com mais limitações.</li>
 <li><a href="/en-US/docs/Web/CSS/Tools">Ferramentas CSS</a>.</li>
</ul>
</div>
</div>
</section>

<h2 id="See_also">Veja também</h2>

<ul>
 <li>Mozilla's <a href="/en-US/Learn/CSS">Learning CSS section</a></li>
 <li>Web languages CSS is often applied to: <a href="/en-US/docs/HTML" title="en-US/docs/HTML">HTML</a>, <a href="/en-US/docs/SVG" title="SVG">SVG</a>, <a href="/en-US/docs/XHTML" title="en-US/docs/XHTML">XHTML</a> and <a href="/en-US/docs/XML" title="en-US/docs/XML">XML</a>.</li>
 <li>Mozilla technologies which make extensive use of CSS: <a href="/en-US/docs/Mozilla/Tech/XUL" title="en-US/docs/XUL">XUL</a>, <a href="/en-US/Firefox">Firefox</a>, and <a href="/en-US/docs/Mozilla/Thunderbird">Thunderbird</a> <a href="/en-US/docs/Extensions" title="en-US/docs/Extensions">extensions</a> and <a href="/en-US/Add-ons/Themes" title="en-US/docs/Themes">themes</a>.</li>
</ul>

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